diff --git a/packages/core/euclid.mjs b/packages/core/euclid.mjs
index 44ab07f1..98c21a11 100644
--- a/packages/core/euclid.mjs
+++ b/packages/core/euclid.mjs
@@ -35,18 +35,18 @@ const right = function (n, x) {
   return result;
 };
 
-const _bjork = function (n, x) {
+const _bjorklund = function (n, x) {
   const [ons, offs] = n;
-  return Math.min(ons, offs) <= 1 ? [n, x] : _bjork(...(ons > offs ? left(n, x) : right(n, x)));
+  return Math.min(ons, offs) <= 1 ? [n, x] : _bjorklund(...(ons > offs ? left(n, x) : right(n, x)));
 };
 
-export const bjork = function (ons, steps) {
+export const bjorklund = function (ons, steps) {
   const inverted = ons < 0;
   const absOns = Math.abs(ons);
   const offs = steps - absOns;
   const ones = Array(absOns).fill([1]);
   const zeros = Array(offs).fill([0]);
-  const result = _bjork([absOns, offs], [ones, zeros]);
+  const result = _bjorklund([absOns, offs], [ones, zeros]);
   const pattern = flatten(result[1][0]).concat(flatten(result[1][1]));
   return inverted ? pattern.map((x) => 1 - x) : pattern;
 };
@@ -128,7 +128,7 @@ export const bjork = function (ons, steps) {
  */
 
 const _euclidRot = function (pulses, steps, rotation) {
-  const b = bjork(pulses, steps);
+  const b = bjorklund(pulses, steps);
   if (rotation) {
     return rotate(b, -rotation);
   }
@@ -139,7 +139,7 @@ export const euclid = register('euclid', function (pulses, steps, pat) {
   return pat.struct(_euclidRot(pulses, steps, 0));
 });
 
-export const e = register('e', function (euc, pat) {
+export const bjork = register('bjork', function (euc, pat) {
   if (!Array.isArray(euc)) {
     euc = [euc];
   }
@@ -216,6 +216,6 @@ export const euclidLegatoRot = register(['euclidLegatoRot'], function (pulses, s
  * .pan(sine.slow(8))
  */
 export const { euclidish, eish } = register(['euclidish', 'eish'], function (pulses, steps, perc, pat) {
-  const morphed = _morph(bjork(pulses, steps), new Array(pulses).fill(1), perc);
+  const morphed = _morph(bjorklund(pulses, steps), new Array(pulses).fill(1), perc);
   return pat.struct(morphed).setSteps(steps);
 });
diff --git a/packages/core/test/euclid.test.js b/packages/core/test/euclid.test.js
index a33ec951..6169abd7 100644
--- a/packages/core/test/euclid.test.js
+++ b/packages/core/test/euclid.test.js
@@ -1,14 +1,14 @@
-import { bjork } from '../euclid.mjs';
+import { bjorklund } from '../euclid.mjs';
 import { describe, expect, it } from 'vitest';
 import { fastcat } from '../pattern.mjs';
 
-describe('bjork', () => {
-  it('should apply bjorklund to ons and steps', () => {
-    expect(bjork(3, 8)).toStrictEqual([1, 0, 0, 1, 0, 0, 1, 0]);
-    expect(bjork(-3, 8)).toStrictEqual([0, 1, 1, 0, 1, 1, 0, 1]);
-    expect(bjork(8, 8)).toStrictEqual([1, 1, 1, 1, 1, 1, 1, 1]);
-    expect(bjork(-8, 8)).toStrictEqual([0, 0, 0, 0, 0, 0, 0, 0]);
-    expect(bjork(5, 8)).toStrictEqual([1, 0, 1, 1, 0, 1, 1, 0]);
+describe('bjorklund', () => {
+  it('should apply bjorklundlund to ons and steps', () => {
+    expect(bjorklund(3, 8)).toStrictEqual([1, 0, 0, 1, 0, 0, 1, 0]);
+    expect(bjorklund(-3, 8)).toStrictEqual([0, 1, 1, 0, 1, 1, 0, 1]);
+    expect(bjorklund(8, 8)).toStrictEqual([1, 1, 1, 1, 1, 1, 1, 1]);
+    expect(bjorklund(-8, 8)).toStrictEqual([0, 0, 0, 0, 0, 0, 0, 0]);
+    expect(bjorklund(5, 8)).toStrictEqual([1, 0, 1, 1, 0, 1, 1, 0]);
   });
 });
 
diff --git a/packages/mondo/mondo.mjs b/packages/mondo/mondo.mjs
index b879f24b..b87a8b58 100644
--- a/packages/mondo/mondo.mjs
+++ b/packages/mondo/mondo.mjs
@@ -21,13 +21,14 @@ export class MondoParser {
     close_curly: /^\}/,
     number: /^-?[0-9]*\.?[0-9]+/, // before pipe!
     // TODO: better error handling when "-" is used as rest, e.g "s [- bd]"
-    op: /^[*/:!@%?+-]|^\.{2}/, // * / : ! @ % ? ..
+    op: /^[*/:!@%?+\-&]|^\.{2}/, // * / : ! @ % ? ..
     // dollar: /^\$/,
     pipe: /^#/,
     stack: /^[,$]/,
     or: /^[|]/,
     plain: /^[a-zA-Z0-9-~_^#]+/,
   };
+  op_precedence = [['*', '/', ':', '!', '@', '%', '?', '+', '-', '..'], ['&']];
   // matches next token
   next_token(code, offset = 0) {
     for (let type in this.token_types) {
@@ -150,9 +151,9 @@ export class MondoParser {
     }
     return children;
   }
-  desugar_ops(children) {
+  desugar_ops(children, types) {
     while (true) {
-      let opIndex = children.findIndex((child) => child.type === 'op');
+      let opIndex = children.findIndex((child) => child.type === 'op' && types.includes(child.value));
       if (opIndex === -1) break;
       const op = { type: 'plain', value: children[opIndex].value };
       if (opIndex === children.length - 1) {
@@ -263,8 +264,10 @@ export class MondoParser {
           // the type we've removed before splitting needs to be added back
           children = [{ type: 'plain', value: type }, ...children];
         }
-        children = this.desugar_ops(children);
-        // children = this.desugar_pipes(children, (children) => this.desugar_dollars(children));
+        // for each precendence group, call desugar_ops once
+        this.op_precedence.forEach((ops) => {
+          children = this.desugar_ops(children, ops);
+        });
         children = this.desugar_pipes(children);
         return children;
       }),
diff --git a/packages/mondo/test/mondo.test.mjs b/packages/mondo/test/mondo.test.mjs
index 6393b10f..a02c6fec 100644
--- a/packages/mondo/test/mondo.test.mjs
+++ b/packages/mondo/test/mondo.test.mjs
@@ -117,6 +117,7 @@ describe('mondo sugar', () => {
   it('should desugar x:y', () => expect(desguar('x:y')).toEqual('(: y x)'));
   it('should desugar x:y:z', () => expect(desguar('x:y:z')).toEqual('(: z (: y x))'));
   it('should desugar x:y*x', () => expect(desguar('bd:0*2')).toEqual('(* 2 (: 0 bd))'));
+  it('should desugar x&y:z', () => expect(desguar('bd&3:8')).toEqual('(& (: 8 3) bd)'));
   it('should desugar a..b', () => expect(desguar('0..2')).toEqual('(.. 2 0)'));
   /* it('should desugar x $ y', () => expect(desguar('x $ y')).toEqual('(x y)'));
   it('should desugar x $ y z', () => expect(desguar('x $ y z')).toEqual('(x (y z))'));
diff --git a/packages/mondough/mondough.mjs b/packages/mondough/mondough.mjs
index e2c6dc9a..a230c3cb 100644
--- a/packages/mondough/mondough.mjs
+++ b/packages/mondough/mondough.mjs
@@ -11,6 +11,7 @@ import {
   chooseIn,
   degradeBy,
   silence,
+  bjork,
 } from '@strudel/core';
 import { registerLanguage } from '@strudel/transpiler';
 import { MondoRunner } from 'mondolang';
@@ -40,6 +41,7 @@ lib['!'] = replicate;
 lib['@'] = expand;
 lib['%'] = pace;
 lib['?'] = degradeBy; // todo: default 0.5 not working..
+lib['&'] = bjork;
 lib[':'] = tail;
 lib['..'] = range;
 lib['def'] = () => silence;